Furnace construction



' May 26, 19412.- s. BURGEss ETAL 2,284,358

FURNAGE CONSTRUCTION 'l Filed March 19,' 1941 2 sheets-sheet 1 BY I A" YATTORNEYS FURNACE CONSTRUCTION Filed March 19, 1941 2 Sheets-Sheet 2Patented May 26, 1942 UNITED STATES PATENT OFFICE FURNACElCoris'rmJc'rIoN Samuel Burgess, South Ozone Park, N. Y., and

Norman Schoeppel, Mexico, Mo., assignors to Nichols Engineering &Research Corporation, New York, N. Y., a corporation of DelawareApplication March 19, 1941, serial No. 884,058

l Claim.

This invention relates to furnaces, and more particularly to an improvedconstruction of ire brick walls in combination with enclosing housingstherefor.V Among other possible uses the invention is especially adaptedfor furnaces of ,types such as used for incineration, purposes.

At one time it wascommon practice to build incinerator furnaces withwalls of lire brick enclosed by an outer wall of heat insulation brick.Such construction involved the diiiiculty that repeated expansion andcontraction. of the lire brick with respect to the insulation brick,would result in serious cracking of the composite wall structure,whereby unsightly apertures would be opened up through the wall,allowing gases to escape, sometimes necessitating frequent repairs, andreplacement of bricks. A later practice involves surrounding such acomposite wall structure with a sheet metal housing strengthened byexternal rods, angle irons or other means. Such wall structures arerelatively expensive and heavy and the external bracing structure forthe metal housing does not present smooth surface and is thereforedifficult to keep clean. Also such cracks as may form in the heatinsulation brick portion within the wall are hidden from view, andaccess thereto for repairs is. difficult.

According to the present invention, the above noted difnculties may beovercome by constructing a Wall of fire brick, using'brick of various Anovel shapes which may be laid in place inexpensively and quickly byunskilledworkmen, this wall being enclosed by a sheet metal shell spacedfrom the fire brick wall, but attached thereto by novel means. Theconstruction is also preferably such that strengthening members for themetal shell, as well as the means for securing the wall and shelltogether, may be located entirely within the space between the lirebrick and the shell. Thus the sheet metal shell presents a smoothexternal surface and the fire brick wall and shell are so interconnectedthat the use of an intervening wall of heat insulation brick may beavoided. Instead, the space between the fire brick wall and shell may befilled with inexpenn Variousfurther and more specific objects, featuresand advantages will clearly appear from the detailed description givenbelowv taken in connection with the accompanying drawings which form apart of this specification and illustrate by way of example certainpreferred forms of the invention. The invention consists in such novelfeatures and combinations of parts as may be shown .and described inconnection withthe apparatus herein disclosed. Y

In the drawings, Fig. 1 is a horizontal sectional view of an incineratorfurnace embodying the invention, the section being taken along the lineI-I of Fig, 2;

Fig. 2 is a vertical sectional view taken substantially along the line2-2 of Fig. 1;

Fig. 3 is a front elevational viewvof the furnace of Figs. 1 and 2 andshowing portions broken away; v

Figs. 4, 5 and 6 are perspective views showing shapes of various formsof fire brick used for the furnace wall structure in accordance withtheinvention; and y Figs. 7 and 8 respectively are front and sideelevational views of a furnace which may be constructed in accordancewith the invention, showing somewhat schematically the manner in whichthe space between the lire brickr and the sheet metal shell of thefurnace may be utilized for a current of cooling air which becomespreheated for introduction at the furnace grate.'

Referring to Figs. 1 and 2 of the drawings in further detail, anincinerating furnace ishere shown having a main fire box I0 separated bya bridge wall II from a combustion chamber I2. A grate of suitable knownconstruction is shown at I3 over an ash'pit I4. An outlet I5 is shown.at the base ofthe combustion chamber and is adapted to be connected bysuitable 'breeching as at I6 to a chimney. The'front wall of the furnacemay be provided Vwithchargingdoors of suitable known construction as atIl, and a clean-out door as at I8.

The fire brick walls of the furnace are shown at I9 enclosed by andspaced from a sheet metal housing or shell 20. The furnace roof maycomprise refractory blocks as at2I suspended'by a structure'of asuitable` known type as at,22 and rections along'the surface of thefurnace wall), are relatively large. These courses of brick of largearea/may preferablyalternate with courses as at 25 (Fig. 2) made upofbrick Which have ya much smaller vertical dimension. The courses 25 mayinclude elongatedbrick. as at 26 V(Fig.

6) alternating with brick such as at 21A (Fig. 4)

As shown,y the vbrick 21V areelongated in a directionperpendicular vtolthe ,wall surface so .that

. portions of these brick as at 28 extend outwardly4substantiallybeyond'the outside surface of .the

'brick in order that the attaching means may be provided therebetween.The attaching means may include bolts as at 31. These bolts mayextendthrough the outstanding webs of the angle irons 36 as shown, andalso `extend through the slots 29 of the protruding brick. Nuts as at 38may be provided to secure the bolts in place and to the angle irons,these nuts preferably however being leftin spaced relationship to theprotrudre brick wall.V 'These portions may be formed with verticalslotsas at 29 for receiving attach'-V ing means for the sheet metalslfiellrga's hereinf after described. Y f* f Figsnl, 5 andytheuppr and flower edges of each of the types otbrick areY As shown in ing brick, soas to permit endwise sliding of the bolts in the'slots 29 and thuspermitting the re brickwallto freely expand or contract inhorizontaldirections parallel to the Wall.

It will be apparent that the slots 29 will permit relative expansion andcontraction of the brick -Wall land shellrin vertical directions. Ifneces- Y sary, the angle irons 36 which are adjacent the preferablyformed with interengaging tongue and`v s groove portions as indicated at30-35 inclusivel These tongue and groove portions willserve to keye'achfbrick of each cour/seV to-Aa plurality Vof brick -both "aboveandAbelow. l' In fact, normally Ye'achoftheY types of brick as'at 26and 21;with the st ructineasshown'; yWill-"thus'be keyed Yto a -total @offouroffthe -large areabrickY of the Y courses above and'beloWgThus,althoughthe bricksuch as at 21 which vprotrude out for at. 'tachinent ofthefurnace 4shellff'arepreferably `made of relatively small crosssection,'yet these may/be so placed as shown in 2 ras'tofbeY keyed toand overlap jtwooi thelarge area brick above, vas Well as twoofthe largeareav brick below. ThusY thesesmaller brick are held securely in placeagainst being vdislodgeidfas a result of any expansion or contractionforces which may inadvertently Vbe appliedA thereto;V

Since a great parto).e thejwall areais Inadeup. 'of' fire brick ofVunusually large area, the wall'may Y be set u p very rapidly. Also thevarious v bricks may be suitably numbered' if desired so'that the wall,maybe built by relatively unskilled ,workr men.Asihereinafterexplained', the sheet metal shell may be attached by meanswhich will acf commodate any'normalexpansion or'contraction Y forces oftheV brick wallin'respectnto Athe shell. Accordingly there will benooute'r wallY structure tendingtoforce the iire bricksout of place.This ffact,-together with thejfact that thejvarious brick .are lsecurelykeyed together, makes vit possible to provide 'a durable wall of'lightweight without the necessityfof using brick of any greatthickness.,

vshowninl the Vvarious iigures, the [exterior vsurface of ^the 'sheetmetal shell or housing may 'be madesrnooth and free ofany strengtheningY Y corners of the housing, .may be formed with slots asvaty 4D forreceiving the bolts 31, these slots V'permitting the front and rearbrick walls of the 'furnace Ytol expand or contract sidewisewith-respect to 'the'sheet metal? shell; v Y t If desired, the: spacebetween the fire brick wall and the sheet metall shelllmay be filledwith suitable insulating material-.suchV as mineral wool,-as shownat'lll0r alternatively, as shownirr Figs. '7-and .8, this 'spacemay beconnectedtoa blower as at 42 forforcing streams of air 'around the spacebetween the brick -walls and the A'sheet Vmoistl material on thegrates.V

WhiltheA-invention has been described in detail with respect toparticular preferred examples, it VwillfbeA understood bythoseskilledrinthe art Jafter understanding the invention, that `various changes andfurtherV modications -may be made without departing from the spirit andv`scope of the,invention;and it is` intended thereor bracing structure.`Thus v the 'outside of the furnace will not only present an attractiveapy pearance, but may be readily kept clean. SinceYV the spacebetweenthe' fire 'brick and the sheet metal shell does not need to beiilled with insulation brick, suitable strengtheningbars' 'orangle ironsas at 36, maybe provided as neededon the Yinside surface of thevshell.,

" 'Ihe vprotruding :slotted portions 28m-of ,they

Various ire brick 21 Will'preferably be located vertical alignmentjandhence the angle irons 3B may preferably be arrangedalong vertical linesadjacent to these V vertical Arows 'ofi protruding fore-in Ytheappended' claim to cover All' such changes and modifications. L Whatisclaimed as new and desired to bese'- Vcured by` Letters APatent is:A

Inan incinerator construction', a Wall of re brick, an o uter sheetmetal 'shell spaced there'- from,rmea11s'secur ing said shell to thewallcom'- vprising brick portions protruding Vfrom the wall surface 'atspaced points and formed' with verti- `cally extending slots, angleironssecured on'the insidesurface of theshell, and bolts `attached'to 'saidangleV irons 'and extending throughsaid'slots, Y said ,slots beingformed with suflicien't clearance with respfe `zttosaidl boltsV wherebysaid' bolts are free for movement lengthwsean'd'vcrticallyfin saidslotsjtoprovide forrel'ative expansion and contraction ofthe walland'shell.

